You could ask if they'll send you an invoice with a more realistic shipping, then either bacs or PayPal it across to them? Worth asking, it might just be a website default they're unaware of/haven't fixed. I've had a couple of international companies sort that for me before.
Nice/trendy new defeet socks
https://defeet.com/pc_combined_results.asp?pc_id=58A7A4A9127C4CDEA17A1FB98720FF9DD
40% off with code CHASE, but shipping to the UK is £50! Hoping to send some to a US family member. £6 a pop is pretty good I reckon!